This application relates generally to an appliance for burning solid fuels, such as wood, corn, pellets, etc., and more specifically for better combustion, more efficient heat distribution, and more economical construction.
With the increased price of energy, especially the fossil fuels, interest in alternative energy sources, mainly wood derived, to heat the interior space of any structure needing a rise in temperature has grown significantly over the past years, largely by moderate income families trying to reduce the bite of inflation, but also by a sizable segment of low income families who simply cannot afford fossil derived fuels.
Wood-burning devices have been well known for a long time, however, their popularity fluctuates. When petroleum fuel is readily available and reasonably priced, wood burning devices use declines. Recently we have seen a resurgence of interest in the use of wood and other bio-mass fuels as a heating fuel. Many of the reasons for the increase include rising petroleum fuel costs, the availability of wood and alternative fuels, and the staggering effects mining, drilling, processing, transporting and the burning of fossil fuels have on the environment. A problem with existing wood-based and other solid fuel burning appliances, however, is their lack of efficiency. That is, they are inefficient in many ways. First, known wood burning appliances must generate more heat than comparable petroleum fired furnaces, in order to adequately warm remote parts of the space in which it is situated. Moreover, existing wood-based and other solid fuel devices generally tend not to burn their fuel as completely as petroleum fueled furnaces and a significant amount of heat escapes directly out the flue. The, e.g., rectangular or square, shape of known appliances also have many design flaws. As a result, the cost advantages of burning wood or solid fuel over petroleum based fuels are diminished.
The resurgence of the interest in burning wood over fossil fuels may also be attributed to the many benefits of burning of wood over fossil fuels. One of the largest benefits of burning wood over fossil fuels is that a person can harvest, process and store wood with minimal harmful affects to the environment. For example, if a pile of wood is spilled, there is no harm to the environment. In contrast, if petroleum fuel is spilled, there is a very large pollution control cost associated therewith. The storing of fossil fuels also requires special containers, whereas wood fuel can simply be piled on the ground or placed inside a structure where it is going to be used. In addition, wood supply is easily accessed by most individuals who are independent and interested in not being dependent on large petroleum corporations who often fluctuate price for the benefit of the corporation and not the individual consumer.
There are many ways in which wood fired and petroleum fired furnaces are not directly comparable. For instance, a pound of wood is not directly comparable to a pound of oil. Oil will flow into a furnace while wood has to be physically loaded after the fire cools down. In this example labor required to deliver the fuel for combustion is not directly comparable from one type of furnace to the other.
There are many ways in which wood fired and petroleum fired furnaces are comparable. Since wood is a simple compound, made up of less elements, less waste is generated. Unburned oil puts hydrocarbons into the air and wood does not. Hydrocarbons from fossil fuels are suggested to be the cause of global warming and not the burning of wood. Trees grow by taking all that is needed out of the air and soil to grow. Thus, when burned, other growing trees will absorb what was put into the air. Oil is nonrenewable.
In comparing wood furnaces with one another. The current obstacle with wood is efficiently burning the wood and distributing the wood's heat in a structure. A problem with existing wood furnaces is their lack of efficiency. Rectangular wood stoves need more fuel to overcome the flaw of their shape. Because square or rectangle wood furnaces have cold spots and hot spots they tend to be operated very hot when re-fueled and a comfortable temperature is trying to be reached. They are inefficient in two other ways. A wood furnace must generate more heat, than petroleum fired furnaces, in order to adequately warm remote parts of the space in which it is situated. Existing wood burning devices generally do not burn their fuel as completely as petroleum fueled furnaces. A significant amount of heat escapes directly out the flue. Rectangular in nature wood burning furnaces have hot spots in the back primarily due to the existence of their corners. As a result, the cost advantages of burning wood or solid fuel over petroleum based fuels are diminished.
From the above, it can be seen what is a need for a device that is easy-to-use, more economical to produce, and efficient to use.